1. Field of the Invention
The present invention relates to a wire harness water cut-off structure for preventing water from invading by way of clearances among wires of the wire harness from a side of an engine room to a side of a vehicle compartment when, for example, the wire harness is wired from the side of the engine room to the side of the vehicle compartment by passing the through hole of a dash panel of an automobile.
2. Related Art
In a background art, when a wire harness is wired between to a side of an engine room and a side of a vehicle compartment by way of a through hole of a dash panel, invasion of water by way of a clearance between the wire harness and the through hole is prevented by arranging a grommet between the wire harness and the through hole.
However, by simply mounting the grommet with an object of sealing the clearance between an outer periphery of the wire harness and the panel through hole, in a case in which when inside of the engine room is cleaned by high pressure water, water is brought to clearances of wires of the wire harness at inside of the engine room, it cannot be prevented that the water invades the vehicle compartment side by way of the clearances among the wires.
Hence, a grommet 20 as shown by FIG. 7 is used. The grommet 20 comprises a main body portion 21 including a main body portion 21 and a cylindrical cone portion 21b and mounted through a through hole 31 of a panel 30 of a vehicle body, a small diameter cylindrical portion 22 continuous to a small diameter side of the cylindrical cone portion, and an inner cylinder wall 23 provided at an inner portion of the main body portion 21 and is constructed by a constitution in which in a state of passing a wire harness W through the main body portion 21 and the small diameter cylindrical portion 20, by filling to solidify a seal agent 25 at an inner portion of the inner cylinder wall 23, clearances among wires of a wire exposure portion W2 exfoliated with a tape are sealed by the seal agent 25.
Further, as a structure of achieving a water cut-off effect without filling a seal agent, there is disclosed a proposal in which an inner portion of a grommet is provided with means for scattering a plurality of wires constituting a wire harness, thereby, water is prevented from invading frontward from the scattered portion (refer to, for example, JP-A-2002-58140).
Further, among these grommets, in order to install the wire harness conveniently within the engine room, there is one in which a bellows tuba is integrated and a strap clamp is attached to a part of the tube so that the wire harness is fixed to the vehicle body with the strap clamp. (See, for example, JP 2000-311534A.)
Meanwhile, the grommet 25 of a type of using the seal agent 25 as shown by FIG. 7, poses a problem that time and labor is taken for an operation of filling the seal agent 25, and therefore, it is difficult to promote a productivity.
Further, in the case of the grommet described in Patent Reference 1, the inner portion of the grommet is provided with the means for scattering a wire bundle, and therefore, the structure is complicated and cost is increased.